Decode the messages before the search takes place. Even plain text messages can be encoded, for instance as quoted-printable, which may disturb the results. However, decoding will slow-down the search.

The exact functionality of this parameter differs per search method, so read the applicable man-page. In any case undef means that details are not collected for this search, which is the fastest search.

DELETE will flag the message to be flagged for deletion. You may also specify your own CODE reference. With an reference to an array, the information about the matches is collected as a list of hashes, one hash per match.

Limit the search to the specified NUMBER of messages. When the NUMBER is positive, the search starts at the first message in the folder or thread. A negative NUMBER starts at the end of the folder. If the limit is set to zero, there is no limit.

Only applicable in combination with a label. How to handle the existing labels. In case of REPLACE, messages which already are carrying the label are stripped from their selection (unless they match again). With AND, the message must be selected by this search and already carry the label, otherwise the label will not be set. Specify OR to have newly selected messages added to the set of already selected messages.

NOT is true for messages which do not fulfil the search. The details output will still contain the places where the match was found, however those messages will complementary set of messages will be labeled and returned.

Are multiparts to be included in the search results? Some MUA have problems handling details received from the search. When this flag is turned off, the body of multiparts will be ignored. The parts search will include the preamble and epilogue.

Check which messages from the FOLDER (Mail::Box) match the search parameters. The matched messages are returned as list. You can also specify a THREAD (a Mail::Box::Thread::Node), one single MESSAGE (a Mail::Message), or an array of messages.

Sometimes we know how only one match is needed. In this case, this searching will stop at the first match. For instance, when limit is -1 or 1, or when the search in done in scalar context.

Fatal error: the specific package (or one of its superclasses) does not implement this method where it should. This message means that some other related classes do implement this method however the class at hand does not. Probably you should investigate this and probably inform the author of the package.